Turbocharger fence ring



Jan. 15, 1963 R. LAZO ETAL TURBOCHARGER FENCE RING Original Filed June16, 1958 2 Sheets-Sheet 1 IN V EN TORS A u is R. L 420 y B ry'ama'n Brib A TTGRNE Y's Jan. 15, 1963 1.. R. LAZO ETAL 3,073,512

TURBOCHARGER FENCE RING Original Filed June 16, 1958 2 Sheets-Sheet 2INVENTORJ' Zua'; R. 1420 y Berg km arish ORNE YS United States Patent3,073,512 TURBOCHARGER FENCE RING Luis R. Lazo, Mentor, and BenjaminBarish, Lyndhurst, Ohio, assignors to Thompson Ramo Wooldridge Inc., acorporation of Ohio Original application June 16, 1958, Ser. No.742,071, now Patent No. 3,010,697, dated Nov. 28, 1961. Divided and thisapplication Nov. 28, 1960, Ser. No. 72,068

2 Claims. (Cl. 230133) The present invention relates to improvements incompressors and particularly to an improved compressor structure whereininternal boundary layer flow back whichfied fabricated structure. Thefence is spiral shaped and projects outwardly along one side of theradial throat of the compressor and projects into an involute shapeddischarge chamber of the compressor to prevent flow back across thethroat.

An object of the invention is to provide an improved compressorconstruction for preventing a boundary layer flow back in the compressedair receiving scroll.

Another object of the invention is to provide a simplified compressorhousing construction with a boundary layer fiow back preventing fenceformed of a stamped flat metal plate attached within the housing.

Other objects and advantages will become more apparent with theteachings of the principles of the present invention in the descriptionsand illustrations of the specification, claims and drawings, in which:

FIGURE 1 is a side elevational view. of a compressor embodying theprinciples of the present invention;

FIGURE 2 is a vertical sectional view taken substan tially along line11-11 of FIGURE 1, and illustrating details of the interior of thecompressor, shown as forming a part of a tmbocharger; and

FIGURE 3 is a detailed elevational view of the fence for preventingboundary layer flow back in the compressor discharge chamber.

As shown on the drawings:

The figures of the drawings illustrate a compressor embodied as part ofa turbocharger as a preferred environment for the compressor. It will ofcourse be understood that the compressor and its features may beemployed in other environments.

FIGURE 1 illustrates a turbocharger embodying the features of theinvention. The turbocharger is enclosed in a housing 12. At thecompressor end, the housing 12 has a housing part 12a secured to a part12b which in turn is secured to another part 120 at the turbine end.Parts 12a and 12b are formed with annular meeting faces and a gasket 14is located between the faces to seal the parts. Bosses, such as 15 and18, may project from the housing parts to receive bolts 19 for securingthe parts 12a and 12b together.

The housing parts 12b and 120 are provided with flanges 12d and Me whichare utilized for clamping the housing parts 12b and 120 together by anannular clamping band 20. The band is provided with inclined inner faceswhich mate with the inclined outer faces of the flanges 12d and 12e tosecurely clamp the parts together, and the band 20 may be loosened forrelatively rotationally shifting the parts 12c and 12b to change therelative positions of the compressor end and turbine end of theturbocharger.

.This variation in rotational position between the ends can beillustrated by reference to FIGURES 1 and 2. In

FIGURE 1, the housing part 12a is provided with a compressed airdischarge outlet fitting 22, and the housing part 120 is provided with alarge inlet boss 24 for hot gases. The conduits to which these fittingsconnect and their positions can be better accommodated with relativerotational shifting of the parts 12a and 120.

Extending axially through the housing is a shaft 26 supported in bearingmeans 28 with seals 30 and 32 along the shaft to prevent the escape oflubricant and to prevent the pressurized air and hot operating gasesfrom entering the lubricant compartments. Lubricating oil is feddownwardly through a passage 33 in the housing part 12b and feeds tolubricating branches 34 and 36, which supply openings in the bearings.The lubricant flows from the bearings down to a lubricant draincompartment 38, and

through a lubricant drain opening 40.

At one end of the housing 12 the parts 12a and 12b form a compressorrotor chamber 42 in which rotates a 'vaned compressor rotor 44. Thecompressor rotor has a hub 46 mounted on the shaft 26 and held thereonby a threaded nut 48. The compressor rotor is provided with impellervanes 50 which force the air centrifugally outwardly to compress it in aknown manner. Air is taken in through an air inlet opening 52 formed byan annular hub 54 on the housing part 12a. The housing part 12b has aradial flat face 56 extending outwardly from the rotor and withanopposing inwardly facing surface 58 on the housing part 12a forms an airflow throat 60' extending radially outwardly for the flow of air fromthe vanes 50 of the compressor rotor 44. The air passes out wardly fromthe throat 40 into an involute scroll air chamber 62. As the compressorrotor 44 forces the compressed air outwardly through the throat 60, itenters the chamber 62 and is discharged out through the fitting 22. Theair flowing outwardly along the flat wall 56tends to circle in thechamber '62 and flow inwardly along the inner surface 64 to interferewith the flow all through the throat 60. This effect may be referred toas back wash or as boundary layer flow back.

A fence 66 in the form of an annular ring is secured to the wall 58beside the throat and projects radially outouter edge to follow thecontour of the involute chamber 62. The ring is interrupted at 620 tofollow the shape of the chamber '62. The fence ring is provided withcircumferentiatlly spaced holes '67 through which are inserted screws 68threaded into threaded holes 70 in the housing part 12a to secure thefence ring 66 in place. The fence ring may also be fastened by weldingor suitable bonding. With the construction shown, the ring may be simplymanufactured by stamping or cutting from flat surfaced sheet metalplates.

If the housing part 12a were made by casting with a fence for-med bycurving the casting material outwardly, this would create numerouscoring and molding problems complicated by shrinkage and cracking. Wehave found that it is unnecessary to exercise the care which would berequired in forming a smooth cast in fence. With the face outwardlytoward a slot or throat 78 through which the heated operating gases flowto drive the rotor. The gases are discharged through an exhaust passage80, formed in an annular hub 82 which is part of the housing part 12c.The operating gases are supplied to the throat through a scroll oroperating gas chamber 84 which extends annularly around the throat 78which supplies the rotor chamber 86.

Within the throat 78 are stator or nozzle vanes 88 secured to a nozzlevane plate or ring 90. As illustrated in FIGURE 2, beside the throat 78and extending axially therefrom is an annular recess 92 in which thevane ring is located. The annular recess also provides a location for aspring ring 94. The spring ring is backed against the wall 92a, andurges the vane ring and vanes 88 against the side 78a of the throat 78.The vane ring has an annular flange 90a with an inner surface 90b thatcenters the spring ring 94.

Thus, the housing part 12c can be inexpensively made, and the vane ring90 and vanes 88 are substantially independent of the housing incontraction and expansion with temperature change. This greatly reducesthe cost of manufacture and improves the safety and operationalperformance, avoiding expensive mountings for vanes and the cost ofconstructions of the type heretofore used.

The spring ring 94, as shown in FIGURE 2, may take various forms, aswill be appreciated by those skilled in the art, but is especiallyadvantageous in being formed with a ring shaped annular back 94a fromwhich facing tongues such as 94b are cut to resiliently projectoutwardly and engage the vane ring 90. This forms an inexpensive, easilyassembled spring arrangement, and the vane assembly and spring assemblycomprise only two parts.

A divided hot gas inlet is provided for improved operation and for thereceipt of operating gas from dual banks of cylinders when theturbocharger is used in an engine having cylinders arranged in banks.The divided inlet is illustrated as preferably formed integrally withinthe hous. ing part 12c, and is illustrated in FIGURE 1. The inletconnector 24 has an outwardly extending flange 24a for connecting a gassupply conduit which is of a size to supply the passage 96 and thepassage 98, and has dual passages.

Operating gas distribution is obtained by the annular extending chamber84 which is divided into two parts. At the upper end, the chamber isdivided by a generally radially extending wall not shown, which istwisted for directing-the flow of operating gases in their radially in-,ward direction toward the nozzle vanes 88, and for preventing crackingwith expansion and contraction. The radial twisted wall divides thechamber 84 into a first part and a second part. The inlet passage 96'supplies the first part, and the passage 98 supplies the second part.The passages 96 and 98 are separated by a twisted wall 102 which issubstantially diametrically opposite the radial 4 twisted wall. Wall102, being twisted, also resists cracking with heat expansion andcontraction.

In operation of the compressor, the rotor 44 is driven by the turbineand air flows in through the inlet 52 and is forced radially outwardlythrough the throat 60 and into the involute compressor chamber 62.Boundary layer flow back of air is prevented by the spiral fence ring 66and the compressed air is discharged through the fitting 22.

Thus it will be seen that we have provided an improved compressorstructure which meets the objectives, advantages and featureshereinbefore set forth. An improved compressor is provided with improvedfiow characteristics and the compressor is inexpensively made withoutcomplications in casting, and the parts are easily assembled.

The drawings and specification present a detailed disclosure of thepreferred embodiments of the invention, and it is to be understood thatthe invention is not limited to the specific forms disclosed, but coversall modifications, changes and alternative constructions and methodsfalling within the scope of the principles taught by the invention.

We claim as our invention:

1. A compressor comprising in combination a cast housing defining acompressor rotor chamber therein with an annular radially extendingthroat opening outwardly from the rotor chamber and with a dischargechamber opening radially and axially outwardly of said throat, a flatsurfaced sheet metal spirally shaped fence ring enlarging in a radialdimension from a small end to a large end and positioned to extendradially outwardly from said throat into said discharge chamber, aradial flat surface on one side of said housing within said throat, andmeans securing said fence ring against said housing surface with oneside surface of the ring in engagement with the housing surface and theother surface forming one side of the throat.

2. A fiow back preventing fence for rigidly mounting at one side of athroat of a compressor having a rotor for delivering air outwardlythrough a radial throat to an involute chamber with an air fiow outlet,the fence comprising a stamped fiat spiral shaped metal ring tapering toa narrow portion at one end and widening to a broad portion at the otherend with a spirally shaped inner edge and a spirally shaped outer edgeto be secured against the housing of a compressor at one side of thethroat and .to project outwardly into the involute chamber of thehousing.

References Cited in the file of this patent UNITED STATES PATENTS2,178,405 Reggio Oct. 31, 1939 2,285,976 Huitson June 9, 1942 2,577,179Buchi Dec. 4, 1951 2,777,632 Kishline et a1. Jan. 15, 1957 2,819,837Loeb Jan. 14, 1958

1. A COMPRESSOR COMPRISING IN COMBINATION A CAST HOUSING DEFINING ACOMPRESSOR ROTOR CHAMBER THEREIN WITH AN ANNULAR RADIALLY EXTENDINGTHROAT OPENING OUTWARDLY FROM THE ROTOR CHAMBER AND WITH A DISCHARGECHAMBER OPENING RADIALLY AND AXIALLY OUTWARDLY OF SAID THROAT, A FLATSURFACED SHEET METAL SPIRALLY SHAPED FENCE RING ENLARGING IN A RADIALDIMENSION FROM A SMALL END TO A LARGE END AND POSITIONED TO EXTENDRADIALLY OUTWARDLY FROM SAID THROAT INTO SAID DISCHARGE CHAMBER, ARADIAL FLAT SURFACE ON ONE SIDE OF SAID HOUSING WITHIN SAID THROAT, ANDMEANS SECURING SAID FENCE RING AGAINST SAID HOUSING SURFACE WITH ONESIDE SURFACE OF THE RING IN ENGAGEMENT WITH THE HOUSING SURFACE AND THEOTHER SURFACE FORMING ONE SIDE OF THE THROAT.